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关键词： BIOLOGICAL systems   LOW-level radiation   RADIOBIOLOGY   DNA  

摘要： This review of low dose-induced whole-body effects, especially cancer, shows: 1) Biological systems appear in hierarchy levels of organization, from atoms to molecules, to cells, to tissues and organs, to the whole system;2) System responses to low-level exposures depend on: quality and number of energy depositions in tissue micromasses (microdoses) being potential triggers to damage and protection;time interval between two microdose events per exposed micromass, that determines cellular responses to the preceding microdose;and responses to microdose events in the system being the target, with the balance between damage and benefit determining the net effect;3) System responses to acute or chronic low-level exposures evolve from damage to the basic molecular level, mainly to DNA of stem cells, and from adaptive responses that may occur in the whole body. Damage may propagate to successive higher levels of organization, meeting protective barriers which may become upregulated by adaptive responses. The balance between damage and protection at each level per individual depends on tissue dose. At single tissue doses below congruent to 0.1 Gy net benefit tends to outweigh detriment. Thus, progression of damage to clinical disease is not linear;4) Quality and extent of system responses are under genetic control. Thus, system net responses expectedly vary among individuals;5) The balance between health risk and benefit of low-level exposure for a given individual may become predictable by gene-expression profiles in control and irradiated cells of this individual;and 6) Clinical trials applying individualized low-level irradiation are justified. (c) 2007 International Society for Experimental Hematology. Published by Elsevier Inc.

关键词： Attention   Dopamine   Hyperactivity   Norepinephrine   SHR   Thyroid hormone  

摘要： Abstract: Attention-deficit hyperactivity disorder (ADHD) is a heterogeneous, highly heritable, disorder resulting from complex gene–gene and gene–environment interactions. The defining symptoms of hyperactivity, impulsivity and impaired sustained attention are not unique to ADHD. It is therefore not surprising that animals with distinctly different neural defects model the behavioural characteristics of the disorder. Consistent with ADHD being a developmental disorder, animal models are either genetic (spontaneously hypertensive rats (SHR), dopamine transporter (DAT) knock-out mice, SNAP-25 mutant mice, mice expressing a mutant thyroid receptor) or have suffered an insult to the central nervous system during the early stages of development (anoxia, 6-hydroxydopamine). It appears that neural transmission is impaired by either direct disruption of dopaminergic transmission or a more general impairment of neurotransmission that gives rise to compensatory changes in monoaminergic systems that are not sufficient to completely normalize neural function. In general, results obtained with animal studies suggest that dopamine neurons are functionally impaired. However, evidence obtained from some animal models suggests that the noradrenergic and serotonergic neurotransmitter systems may be the target of drugs that ameliorate ADHD symptoms. [Copyright &y& Elsevier]

关键词： ascidian   Didemnum   distribution   fouling   Georges Bank   invasive species   nonindigenous   Stellwagen Bank   Tillies Bank   tunicate  

摘要： Didemnum sp. A is a colonial ascidian with rapidly expanding populations on the east and west coasts of North America. The origin of Didemum sp. A is unknown. Populations were first observed on the northeast coast of the U.S. in the late 1980s and on the west coast during the 1990s. It is currently undergoing a massive population explosion and is now a dominant member of many subtidal communities on both coasts. To determine Didemnum sp. A's current distribution, we conducted surveys from Maine to Virginia on the east coast and from British Columbia to southern California on the west coast of the U.S. between 1998 and 2005. In nearshore locations Didemnum sp. A currently ranges from Eastport, Maine to Shinnecock Bay, New York on the east coast. On the west coast it has been recorded from Humboldt Bay to Port San Luis in California, several sites in Puget Sound, Washington, including a heavily fouled mussel culture facility, and several sites in southwestern British Columbia on and adjacent to oyster and mussel farms. The species also occurs at deeper subtidal sites (up to 81 m) off New England, including Georges, Stellwagen and Tillies Banks. On Georges Bank numerous sites within a 230 km(2) area are 50-90% covered by Didemnum sp. A;large colonies cement the pebble gravel into nearly solid mats that may smother infaunal organisms. These observations suggest that Didemnum sp. A has the potential to alter marine communities and affect economically important activities such as fishing and aquaculture. (c) 2006 Elsevier B.V. All rights reserved.

关键词： 分子生物学技术   快速检测   病原体   水产养殖动物   免疫学方法   酶联免疫吸附试验   应用   水产养殖病害  

摘要： 在动植物病原体的检测中，方法学历经了生物培养、显微镜观察、生化检测、免疫学到分子生物学几个阶段的变更，朝着更特异、更快速、更便捷、更安全、集成化、微量化、定量化、费用低廉化的方向发展。传统病原检测主要依据致病病原体在介质或细胞中的培养、分析病原体表型或血清型特征，或采用组织学检测病原体对宿主器官的影响。这类方法耗时、特异性和灵敏度低，远远不能满足日常快速检测工作的需要。免疫学方法可以在一定程度上缩短检验时间，就灵敏度而言，酶联免疫吸附试验（ELISA）要高于免疫荧光、反向免疫凝胶电泳和免疫扩散，是最常用的免疫学检测病原体方法。但是许多病原体之间存在交叉反应，从而使免疫学方法受到很大局限性。近10a来，分子生物技术的快速发展极大提高了水产养殖病害诊断水平。

关键词： 底栖动物   水质   生物学评价   松花江  

摘要： 1999—2005年对松花江下游江南屯断面及支流梧桐河断面进行了11次底栖动物生态调查.调查期间共发现底栖动物39种,其中水生昆虫21种,软体动物12种,环节动物4种,甲壳动物2种.江南屯与梧桐河底栖动物的种类组成呈现显著差异,在发现的39种底栖动物中,仅有14种于两断面都有分布.分布于江南屯断面的主要底栖动物及其出现率为:纹石蚕100%,箭蜓80%,黑龙江短沟蜷80%,钩虾80%,二尾蜉60%,细蜉60%,灯蛾蜉60%,东北田螺60%.分布于梧桐河断面的主要底栖动物及其出现率为:黑龙江短沟蜷100%,东北田螺100%,扁蛭100%,珍珠蚌60%.从栖息密度来看,梧桐河断面中软体动物密度最大,优势种为东北田螺,江南屯断面则以水生昆虫占优势.此外,两断面的底栖动物数量在不同年份也存在显著变化.水质生物学评价结果表明,梧桐河断面多年处于中污染状态,江南屯断面的污染状况在总体上较梧桐河断面轻,这主要是由于梧桐河断面高负荷的耗氧有机物引起水体中溶解氧含量匮乏,从而导致底栖动物的生存条件严重恶化.

关键词： 浮游动物   群落结构   多样性指数  

摘要： 对渤海湾浮游动物群落结构进行了分析,结果表明,渤海湾浮游动物全年平均丰度为2651.5个/m3,最大为7 047.2个/m3,最小为328.9个/m3。其中桡足类在各航次中占据大多数,是数量的主要构成者,且呈明显的季节变化。浮游动物主要的高峰期出现在春季,此外,夏秋两季各有一个小高峰。小拟哲水蚤、太平洋纺锤水蚤、长腹剑水蚤和中华哲水蚤是春季的优势种;强壮箭虫和真刺唇角水蚤是夏季的优势种;小拟哲水蚤、强额拟哲水蚤和长腹剑水蚤是秋季的优势种。结合多样性指数的分析方法对渤海湾水质进行评价,结果为:由于陆源排放和养殖业的发展水体受到相当程度污染。

关键词： 动物生物学   课程   教学改革  

摘要： 在科学技术迅猛发展及教育体制改革不断深入的形势下,高校如何进行教学改革,以适应2l世纪高素质人才培养的需要,是摆在高校教师面前的一个重要问题.我们在长期教学实践的基础上,学习并借鉴了国内兄弟院校的改革经验,对《动物生物学》课程教学方法、手段和课程评价等环节进行了积极的改革与探索.

关键词： 分子生物学技术   水产养殖   细菌性病原   核酸杂交   基因芯片PCR技术   检测  

摘要： 回顾了核酸杂交、基因芯片、PCR等分子生物学技术在水产养殖动物细菌性病原检测中的应用,并对水产养殖细菌性疾病诊断技术的发展方向作了展望。

关键词： biopsy   liver   research   surgery  

摘要： This report describes the author's experiences in participating in avian research during 3 field seasons in remote areas in Prince William Sound (PWS), located in south-central Alaska. Veterinary support was needed to biopsy the livers of nestling and adult pigeon guillemots (Cepphus columba) and adult black oystercatchers (Haematopus bachmani). These surgeries were part of larger research studies investigating guillemot and oystercatcher populations and possible continued exposure to residual crude oil in the marine environment after the Exxon Valdez oil spill in PWS in 1989.

关键词： VIVIPAROUS LIZARD   ALPINE LIZARD   NEW-ZEALAND   PHYMATURUS-PATAGONICUS   SCELOPORUS LIZARDS   GROWTH   CYCLE   SIZE   AGE   POPULATION  

摘要： The southern-most nocturnal Gecko Homonota darwini from Patagonia, Argentina, exhibits a long cycle of gametogenesis, and females usually skip a year of reproduction. This annual to biennial cycle for females and a fixed clutch size of one egg results in a mean annual reproductive output of 0.75, which is one of the lowest values found in lizards. The life-history traits, summarized here for H. darwini, are closer to phylogenetically distant species from similar latitudes (Argentina, South Africa, New Zealand, and Tasmania) than with congenerics from lower latitudes in Argentina. We postulate that the affinities found among different reptile lineages living at similar latitudes in the Southern Hemisphere are the result of convergence. The short activity seasons and the low mean temperatures seem to select for prolonged reproductive cycles, low reproductive output, long lifespan, late maturity, and enhanced parental care of fewer offspring.